Thomas bqyd



T. BOYD.

- Chimney Cowl.

Patented Sept. 14, 1869.

IVLTNESQES N, PETERS, PNOTOJJTKDGRAPHER. WASHINGTON ll C,

' thereto.

brick portion of the chimney. casing is to he, say, (3) three or (4) four inches greater THOMAS BOYD, or CAMBRIDGE, MASSACHUSETTS.

Letters Patent No. 94,864, dated September 14, 1869.

CHIMNEY-TOP.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern Be it known that I, THOMAS BOYD,.of Cambridge, in the county of Middlesex, and Stateof Massachusetts, have invented a' new and useful Improvement in Chimney-Tops and Ventilating -Flues and Caps; and Ido hereby declare that the .following is a full, clear, and exact description of the same, reference being had to the annexed drawings, making part of this'speciapplied to a building for that purpose, and having within the air-chamber a coil of pipe;

Figure 4 is a horizontal section on line was of fig. 1; Figure5 is a modification of the hot-air chambers surrounding the same;

and 1 Eigure 7 is a horizontal section on line z z of fig. 2.

Corresponding letters refer to corresponding parts in the several figures.

This invention relates. to chimney-tops and ventilating-flues and caps, and consists in so combining and arranging the parts as to form achamber around the interior funnel, whichbecomes filled with heated air, and thus increases the draught through the j funnel.

A, in the drawings, represents a chimney and ven-l tilating-flue, with my improved capor top applied This chimney and flue is to-he of any approved form of construction, and of any size, to suit the views of the constructor.

B represents a casing, or tapering column, which .may be made of cast or sheet-metal, or of" brick, clay,

pottery, or any other suitable material its base being so constructed as to fit on or upon the top of the The diameter of this than the flue in the chimney, and is to extend above the top thereof, say, two or three feet, and is for the purpose of forming the outside wall of the hot-air chamber 1). This casing may be square, round, 00-

tagonal, or of any desired configuration, and should be,-at its upper end, about one inch larger than the exterior of the pipe or funnel O, and be provided with an 'inwardly-pr'ojecting flange, which will reach to and form an air and Water-tight joint with the surface of such funnel. p I 0 represents apipe or fnnnehthe-dimensions of Figure 6 is a horizontal section on line @131 of fig. 3; p

which are to be such, in its cross-section, that it will fit the flange formed upon the interior of the casing B andthe fine of the chimney. -Its sides are to be parallel, and it should extend-down into the flue in the chimney frpm one to three feet, or more, while its upper end projects two; three, or more inches above the top of the casing; itbeing provided near its upper end with a projection tofit upon thesame, and thus prevent its moving downward.

.- D represents the hot-air chamber, which is formed or bounded by the casing B upon its outside. and the funnel 0 upon its inside. This chamber, as will be I seen, extends from the point where the casing. B. restsupon the chimney K to the point where the flange thereon comes in contact with the pipe 0, thus furnishing a chamber for heated air the whole height of that portion of the pipe which extends above the chimney, and also at the corners of the chimney around. that portion which terminates therein. this air-chamber is to heat the pipe through which the products of combustion pass to the atmosphere, and thus to give them a more rapid movement at that point, and thus, as a consequence, to increase the draught.

E represents a cap or cowl, which, in some cases, I

propose to use, (although the chimney-top may be regarded as complete withoutit,) for the purpose of still further increasing the draught, and preventing the wind from blowing down into the chimney. This cowl is made at an acute angle, sutficiently high to allow the'discharge-pipe to extend up into it, and se-" cured to a rod, having a not upon its upper end, as shown in fig. 2, or it may rest 'upon such nut, as shown in fig. 3.

F,"'in fig. 2, 'represents, a coiled pipe, which, in some instances,- I propose to use for the purpose of causing the heated products of combustion to pass directly from the chimney-flue to the chamber 1).. I have described the pipe or funnel C as being cy1 .indrical in form, and thechamber I). as an annular form of segments of a circle; or a cylindrical pipe may be yused for the casing, which pipe may enter the chimney onlya short distance, or only far enough to receive a tight joint in the chimney, and a square or other formed pipe be inserted therein, so as to have a series of chambers on the sides thereof. i

It is apparent that when the device is used as a ventilator only, and the wind is depended upon as the agent for producing .the draught, the casing B and pipe F may be dispensed with, and only the funnel O and cap E used to produce the required result.

flaving thus described my invention,

The effect of.

What I claim, and desire to secure by Letters Patchimney A, substantially as and for the purpose set ent isforth.

1. The combination and arrangement of the pipe In testimony whereof, I have signed my name to this or funnel O, casing B, and cap E, substantially as and specification, inthe presence of two subscribing wit-- for the purpose set forth. nesses.

2. The combination of the funnel O, casing B, and THOMAS BOYD. coiled pipe F, substantially as and for the purpose set I forth. Vitnesses 3. The combination of the chimney-top, consisting JOHN N. BARBOUR, of the funnel O, casing B, and cap E, with the flue or ALFRED L. BARBOUR. 

